Question

Giúp mình vs ạ

Answer 1

\(a,=\dfrac{7}{5}\cdot\dfrac{9}{7}\cdot\dfrac{8}{6}=\dfrac{12}{5}\\ b,=5\sqrt{15}+10-2\sqrt{15}=3\sqrt{15}+10\\ c,=25\sqrt{3}-12\sqrt{3}+12\sqrt{3}=25\sqrt{3}\\ d,=\dfrac{2-\sqrt{5}+2+\sqrt{5}}{\left(2+\sqrt{5}\right)\left(2-\sqrt{5}\right)}=\dfrac{4}{-1}=-4\)

Answer 2

c: \(=25\sqrt{3}-12\sqrt{3}+12\sqrt{3}=25\sqrt{3}\)